const add = require("./add");
let result = add(10, 20);
console.log(result);
//减法
const sub = require("./sub");
let result2 = sub(10, 20);
console.log(result2);
// 乘法
const mul = require("./mul");
let result3 = mul(10, 20);
console.log(result3);
// 除法
const division = require("./division")
let result4 = division(10, 20);
console.log(result4);